A280753 Denominators of triangle related to enumeration of minimal 2-covers of a labeled n-set.
1, 3, 3, 7, 2, 7, 15, 5, 21, 15, 31, 3, 651, 186, 31, 63, 7, 651, 651, 651, 63, 127, 4, 11811, 15748, 11811, 762, 127, 255, 9, 66929, 602361, 602361, 10795, 32385, 255
Offset: 1
Examples
Triangle begins: 1, 1/3, 1/3, 1/7, 1/2, 1/7, 1/15, 3/5, 10/21, 1/15, 1/31, 2/3, 865/651, 71/186, 1/31, 1/63, 5/7, 2630/651, 1427/651, 181/651, 1/63, 1/127, 3/4, 163133/11811, 306553/15748, 36667/11811, 145/762, 1/127, ...
Links
- Octavio A. AgustÃn-Aquino, Archimedes' quadrature of the parabola and minimal covers, arXiv:1602.05279 [math.CO], 2016.